The present invention relates to a method for measuring the thickness of the wall of a high-temperature furnace.
In a high-temperature furnace such as for refining, melting or heating metals during the manufacture thereof, it has been a common practice to provide a cooling cell assembly for protecting the furnace body inside the outermost iron shell with a layer of mortar functioning as a cushion between the shell and the cooling cell assembly, to circulate cooling water through the cooling cell assembly, and further to provide a wall of refractory bricks in the furnace inside the cooling cell assembly so as to keep the cooling cell assembly from being exposed directly to a high temperature. In such a furnace, however, after a long time of operation the refractory bricks are occasionally damaged to expose the cooling cell assembly to the high temperature within the furnace. In such cases, the cooling cell assembly itself may be damaged by melting due to the high temperature or by wearing due to the solid bodies within the furnace. In the high-temperature furnace, accordingly, it is very important and indispensable to monitor the wear of the cooling cell assembly from time to time not only for the smooth operation of the furnace but also for prevention of damage to the furnace body.
The heretofore employed method for monitoring the wear of the cooling cell assembly was to insert a sounding rod into an inspection hole in the wall of the high-temperature furnace to thereby measure the thickness of the cooling cell assembly or the thickness of the entire furnace wall. Since the inspection hole had to be sealed with mortar during furnace operation and the mortar had to be removed for measurement, it was sometimes difficult to determine the position of the end face of the inspection hole when the mortar was not sufficiently removed and deposits on the furnace wall tended to interfere with accurate measurement. Another disadvantage of the prior art method was that the measurement according to the method required a special skill and a keen sense on the part of the measurer.